A scroll centrifuge is used to separate the solid and liquid phases of a slurry, such as coal fines. However, many slurries contain hard, abrasive solids which often cause wearing, plugging and breaking of the screen sections of scroll centrifuges. The basket of prior scroll centrifuges comprises a screen section which typically has been formed from stainless steel screen elements welded to circumferential ribs. The screen elements form an inner surface of substantially conical form, over which the solids are moved toward an outlet by the helical scroll. The basket which is formed out of relatively thin material is supported by a cage device which permits the screen portion to withstand the very high g-forces created when the centrifuge is operated at high rpm.
Prior art scroll centrifuges as referred to above have had extensive commercial use despite certain shortcomings, such as rapid wearing away of the screen section of the basket, particularly when exposed to hard, abrasive solids, as, for example, in the dewatering of coal fines. Typically, when the screen section is either broken, plugged or worn, the centrifuge is disassembled and the basket is replaced. This results in repeated maintenance and costly replacement of parts. The use of tungsten carbide ligaments in the screen portion of a different type of centrifuge, a screen bowl centrifuge, is disclosed in U.S. Pat. No. 4,983,289.